In: Nursing
1.ANSWER
Fetal assessment is the determination of the wellbeing of the fetus.
the techniques and procedures include
* medical and nursing histories and physical examination of the mother
* asssays of amniotic fluid obtained by amniocentesis
*ultasonography
*chemical assessment of placental function
*electronic and ultrasonic fetal heart rate monitoring
*chororionic villus sampling
extensive and thorough assessment of the health status is indicated whenmaternal characteristics , obstetric complications and familial and genetic factors place the fetus at risk.
amniotic fluid assay is most often done to establish diagnosis of a genetic disorder, to monitor the fetus sensitised against the mothers RH factor or te determine th e fetal lung maturity. cells floating in the amnioyic fluid sample ca be examined to detect genetic disorders caused b by chromosomal abnormalities and to detect genetic disorders caused by chromosomal abnormalities and to detect certain metabolic aberrations. Neural tube defects such as spina bifida and anencephaly are detected by analysing the amniotic fluid for alpha fetoprotein . when an open neural tube defect is present , the amount of alpha feto protein can be increased as much as eight times the normal value
The amniotic fluid can be assayed for bilirubin , an indicator of the severity of Rh incompatibility between maternal and fetal blood. fetal lung maturity can be assessed by evaluating the presence of pulmonary surfactant , a phospholipid protein, in the amniotic fluid. the principal constituents lecithin and sphingomyelin ca n be evaluated by measuring the lecithin -sphingomyelin ratio in a sample of amniotic fluid. in general , a ratio greater than 2:1 indicates that the fetal lungs are mature and the newborn infant is not likely to develop respiratory distress syndrome of the newborn.
Ultrasonography is a non invasive technique helpful in diagnosing unusual fetal presentations , placenta previa, multiple pregnancy and feta abnormalities such as hydrocephalus and hydronrphrosis.it also can be used to trace fetal growth by periodoc measurement of the biparietal diameter of tthe head of the fetus, femur length or head abdominal circumference ratio
Chorionic villus sampling is a technique by which a small is obtained from the fetal portion of the placenta by aspiration through the crvical canal. it can be used for diagnosis of genetic abnormalities as earlyas first trimester
Chemical assessment of nutritive and respiratory functions of the placents can be accomplished by determinig the amountof the hormones estriol in the maternal blood or urine. throughout gestation a normally functioning placenta produces increasing amounts of estirol value ,the precursors for the production of which are provided by the fetal adrenal glands. thus a normal estriol value in maternal blood or urine indicates that both th e pacenta and the fetus are healthy.
Non invasive monitoring- the fetal heart rae is measured using the techniques of ultrasonography. evaluations of this kind provide good data on the fetalheat rate . the duration and relative strength of uterine contractions and the length of intervals between them can be measuresd externally by placing a tokodynamometer on the mothers abdomen at the site of greates tuterine activity.
Invasive monitoring : invaisve tecchniques of fetal and maternal monitoring require direct access to the fetus and amniotic sac athrough dilated cervix.direct electrocardiography of teh fetal heart is accomplished by attaching an electrode to teh fetal presenting part.
Non stress test : this test relies on spontaneous fetal activity rather on oxytoxcin induuced fetal movment to asess fetal response to uterine contractions.fetal heart rate is monitord externally and corelatedwith fetalactivity.
Thus fetal assessment helps to determine placental perfusion and fetal wellbeing links teh concept of reproduction with the concept of perfusion.